Walking on a pebble route to allow the pebbles to massage the soles of the feet and stimulate the nerve system of the feet is a well-known informal therapeutic method. The principle of the therapy is based on traditional Chinese medicine in which the human body is considered full of "cavities" under the skin and by stimulating these "cavities", the human body can increase its ability of restoring health. Acupuncture, which is well accepted as a useful therapy, is an example of the application of such a "cavity" principle.
Although further experimentation may still be needed to prove the "cavity" principle, massage of the soles of the feet by stimulating the "cavities" located therein is still very important for health. This is because the soles of the human feet are subject to daily constraint within the limited space provided by shoes, especially for those living in urban areas. Thus, the soles of the feet are under great strain which should be suitably released, for example, by massage to keep the feet healthy.
Massaging the soles of the feet to release the pain and strain that such soles are subject to is very useful. Thus, it is more popular nowadays that people use the foot massage devices to massage and release the strain of the soles of the feet.
The foot massage device of the previously-mentioned kind may have a flat base on which a plurality of upward projections, in the form of pebbles, are mounted. A person walks on this structure so as to have the soles of his or her feet massaged by the pebble-like projections. An example of such a prior art structure is shown in FIG. 3 of the accompanying drawings, in which a number of pebbles of suitable sizes are partially buried in a solid substrate, and thus fixed in the ground for people to walk thereon with bare feet.
A disadvantage of such a fixed pebble massage device is that the pebbles are not floating. The pebbles are not movable to comply with the size and shape of each individual's feet that step on them, so that damage may be caused by excessive stimulation of the soles by the fixed pebbles.
Further, since the pebbles are generally not resilient, they may cause injury to people falling down on them, especially for the knees and the elbows.
Another disadvantage of such a fixed type foot sole massage device is that it requires quite a large space to lay and fix the pebbles, for example, to form a pebble route of a substantial length in a park. Such a fixed device is difficult to move to desired locations.
It is therefore desirable to provide a massage device for the soles of the feet of such kind which overcomes the deficiencies of the conventional fixed type foot massage device.